George m



(No Model.)

G. M. HATHAWAY & E. B. STOCKING.

. CUPOLA 0R BLAST FURNACE.

N0. 404.908.v PatentedJune 11, 1-889.

N. PETERS PhomLirhu n hnr. Wnshipglon. ac

UNITED STATES PATENT FFICE.

GEORGE M. IIATHAWAY, OF NEW YORK, N. Y., AND EDGAR B. STOCKING, OF WASHINGTON, DISTRICT OF COLUMBIA.

CUPOLA OR BLAST FURNACE.

SPECIFICATION forming part of Letters Patent No. 404,908, dated June 11, 1889.

Application filed October 11, 1888. Serial No. 287,834. (No model.)

To all whom it may concern:

Be it known that we, GEORGE M. HATHA- WAY, of New York, N. Y., and EDGAR B. STOCKING, of IVashington, in the District of Columbia, both citizens of the United States, have invented certain new and useful Improvements in Oupola or Blast Furnaces, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention has relation to cupolas, or, more technically, blast-furnaces for the reduction or smelting of ores, the object in the main being to provide a construction adapted to the use of natural gas as a fuel.

Other objects and advantages of the invention will be hereinafter described, and the novel features thereof will be particularly pointed out in the claims.

Referring to the drawings, Figure 1 represents in central vertical section a blastfurnace constructed in accordance with the invention. Fig. 2 is a horizontal section on the line a: x of Fig. 1.

Like letters of reference indicate like parts in both the figures of the drawings. -A represents the primary furnace; in which the charge of ore (in alternate layers with limestone or other flux, according to the nature of ore employed) is fed through the charging-door A. Fire-brick B or other suitable material is used as a lining for the furnace, and these are backed by the cast or other cylinder 0 of iron,which serves the purpose of retaining the lining against expansion.

WVithin the cylinder 0, or outside thereof, is

a gas passage or space D. On the right of Fig. 1 is shown a gas-passage D in the cylinder O, which communicates with gas-passages B formed in the lining B. On the left.

latter case a water-supply pipe F is used, and a discharge-pipe F may be connected with a similar water-jacket employed in the secondary furnace, as hereinafter described.

Air-tubes G are arranged at various points to communicate with the gas space or passage for the purpose of assisting the complete combustion of the fuel.

NVhen water is used, it is maintained within the space E at about on a level with the supply-pipe, as indicated by dotted lines in Fig. 1, thereby utilizing the upper portion of the space E as a steam-chamber, from which a steam-pipe II extends to an ejector I. A branch pipe or pipes H may be arranged to serve additional injectors I, and each may be provided with a controlling-valve H The bottom of the furnace is hinged, as at A and provided with a fastening bolt or device A to give access for cleaning purposes. Pillars (or it may be masonry) are employed for sup porting the primary furnace.

A represents the throat of the primary furnace, and this is arranged to deliver the molten metal into a secondary furnace J, comprising the refractory lining B, which may or may not be provided with the gas-passages B,

communicating with the gas-space D, which is surrounded by the Water-space E and is provided with a throat J, the end or tap-hole of which is adapted to be closed by fire-clay, which is removed when it is desired to draw the metal from the said secondary furnace.

J 2 is the cover of the secondary furnace, which may be hinged, as at J at one edge and provided with a fastening device J at the opposite edge. Below the secondary furnace is a fire-box L, with which the gas-space D communicates. A gas-passage D is provided,

which communicates with the upper end of the annular gas-space D of the secondary furnace and with the lower'end of the gas-space of the upper furnace, while a similar passage E affords communication between the waterspace of the primary furnace and that of the secondary furnace.

The compound injectors each consists of a gas-pipe I, within whichis arranged a steampipe H, or a branch H thereof, and these are concentrically arranged in an air-funnel 1 This fire-box is preferably situated directly beneath the secondary furnace, as shown in the drawings; but we do not limit ourselves to this detail of construction, as any fire-box in close proximity to the" secondary furnace will accomplish the purpose of that shown and described. The main point is that the gases entering at this fire-box shall not be allowed to come into contact with the molten metal in the secondary furnace.

It will be seen that an injector-burner is provided at the base of the primary furnace and arranged to communicate with the lower portion thereof to constitute the same a m elting-zone, the portion above being practically a heating and drying zone which terminates at the charging-door.

The operation and manner of applying fuel are,as follows: After being charged with ore and a suitable fluxing material gas is introduced into the burner arranged at the base of the primary furnace, and steam, after having been formed, may be introduced by the pipe II, or before such forming of the steam it may be supplied from any other suitable source, so that the gas, air, and steam are comingled and injected, the former of course being ignited, into the primaryfurnace to reduce the ore. At the same time, and when the furnace completely in operation, the burners I at the base of the secondary furnace are in operation and the products of combustion encircle the secondary furnace, from thence passing into the gas-passages of the primary furnace, and from thence into the dome M and uptake M. through an opening or openings M The air-pipes G supply any lack of oxygen to perfect the combustion of any portion of the fuel which may have arrived at said airtubes without being consumed. The provision of the gas-passages B in the bricks B is for the purpose of conducting the burning gaseous fuel as closely as possible to the contents of the blast-furnace and to prevent direct contact of the fuel \viththe metal therein. As fast as the ore becomes melted in the primary furnace it runs into the secondary furnace, so that the cooling effect of the superimposed ore is obviated and the molten metal as it collected in the secondary furnace is subjected to the more intense heat of the burners, and when a sufficient quantity collected therein the tap-hole may be opened and the metal withdrawn. Now it will be noticed that by the increased number of burners arranged at the secondary furnace an intense heat can be maintained therein, while the surplus heat is conducted to and up around the primary heating-furnace, so that a primary heating of the ore preparatory to the smelting action of the burner I may be accomplished therein. The object of the burners there shown is preferably to be employed in the connncncement of the operation of smelting, although it is apparent that it may, if desired, be used either alone or supplemented. by others to hasten the entire operation and increase the capacity of the blast-furnaces as a whole.

The prevention of direct contact of the fuel with the metal in the secondary furnace is an important feature of the invention in that the character of the iron is not affected thereby in a manner to increase the carbon beyond the desired percentage, and yet as some carbon is required to reduce the magnetic oxide to the metallic state and to unite with the iron to form cast-iron a burner (or burners) is provided to conduct the fuel while ignited into direct contact with the ore and molten metal in the primary furnace. As soon as sufficient carbon has been taken up and sufficient air injected into the primary furnace to produce the molten metal that metal is immediately conveyed into the secondary furnace, where it is subjected to intense heat without contact, while any gases evolved pass upwardly through the throat of the primary furnace to the cupola itself, and finally to the uptake.

Having described the invention, what is claimed is- 1.. In a blast-furnace, a primary and a secondary furnace communicating with each other by the throat of the former and each surrounded by a shell forming a gas-chamber, a communicating passage from the gas-chamber of one furnace to that of the other, and a burner or burners independent of thefurnacc arranged at the secondary furnace, substantially as specified.

2. In a blast-furnace, a primary and secondary furnace communicating with each other by means of the throat of the former, which furnace consists of a refractory lining, an annular shell forming a gas-chamber and an outer shell forminganon-conductingchamber, and burners independent of the furnace arranged at the secondary furnace, substantially as specified.

In a blast-furnace, a compound furnace comprising a primary furnace surrounded with gas and water chambers and having its throat communicating with a secondary furnace provided with annular gas and water spaces communicating with the gas and water spaces,respectively, of the primary furnace, and a fire-box communicating with the gasspaccs of the secondary furnace and provided with a burner or burners, and a steampipe extending from the n on-conductin g space of the primary furnace to the burners, substantially as specified.

4-. In a blast-furnace, a compound furnace comprising a primary furnace arranged above and at one side of a secondary furnace and communicating therewith by its throat, said primary furnace being provided with a surrounding combustion or gas chamber, and a communicating passage leading from the gas chamber of one furnace to that of the other, and a burner independent of the furnace arranged at the secondary furnace, substantially as specified.

ITO

5. A compound blast-furnace consisting of a primary furnace communicating by its throat with a secondary furnace, each provided with lining-brick and with surrounding communicating gas and water chambers, a communicating fire-box and a series of burners projected therein, and a burner communicating directly with the interior of the pri mary furnace, substantially as specified.

6. A blast-furnace consisting of a primary furnace arranged above and at one side of and comlnunicatingwith a secondary furnace, and gas-burners independent of the furnace arranged against an outer wall of said secondary furnace, substantially as specified.

In testimony whereof we affix our signatures in presence of two witnesses.

GEO. M. HATHAVVAY. EDGAR B. STOCKING.

YVitnesses to signature of Geo. M. Hathaway:

ED. MEADE, JOHN MOORE.

l/Vitnesses to signature of E. B. Stocking:

H. SUTHERLAND, W. S. DUVALL. 

